First and foremost is repeal the 17th Amendment. From there, Mark Levin's Liberty Amendments should be considered, for they would super-federalize the government and prevent executive branch lawmaking.
Second, begin repeal, or rather overturn dozens of supreme court decisions by constitutional amendment. Fag marriage for starters.
The effect would revolutionize government. Scotus would be put on notice that a higher earthly power exists to judge them. Social justice by scotus decree would come to a screeching halt.
We can already do that via Congress, just like they did prohibition. Trump would ask Congress to start the process to repeal the amendment.
Second, begin repeal, or rather overturn dozens of supreme court decisions by constitutional amendment.
So someone takes the amendment(s) to the court system and says we think this/these amendment(s) is/are unconstitutional. It winds itself all the way up to the Supreme Court and they rule it unconstitutional. The amendment is then tossed before it is ever enacted.
You see therein lies the problem, the Constitution gives the Supreme Court the power to interpret the Constitutionality of a law. It can't make or enforce laws, but only rule on them. That's why when we allowed abortion to become law, or gave same sex marriages constitutional protection, it now falls on the court system to reverse itself, and constitutionally that becomes hard, due to precedence. It's a kind of catch-22 legally. It can be done but the makeup of the court is everything, and it may even require judicial activism. I myself think the argument should be that the Supreme Court in affect made law, which is itself unconstitutional. They in fact only ruled on the law that banned all abortions. Which means they cannot make it law that all abortions are legal upon demand at anytime during the pregnancy.
But again these can all be done by Congress. A Constitutional Convention is not necessary. What is necessary is for there to be a overwhelming hue and cry from the populace to motivate Congress to start the process. If they then fail to do so, then a Constitutional Convention may indeed be in order as a recourse of last resort. Realize though that one has never met the requirements needed to compel Congress to call one. Which means they are very hard to get enough momentum to actually go that route.